The present invention generally relates to procedures and devices for angioplasty treatments and the like. More specifically, the invention relates to improvements in catheter systems and angioplasty procedures for treating stenoses in blood vessels and other vessels of living bodies.
Balloon angioplasty procedures have been shown to be efficient and effective treatments to open arteries and other body passages occluded with plaque. These procedures generally involve insertion of a balloon catheter into the occlusion, or stenosis. The balloon, which is located at or near the distal end of the catheter, is then inflated, compressing the plaque to the arterial wall and dilating the stenosis or lesion within the artery, for example.
Often balloon catheters cannot be easily negotiated through branching vessels such as arterial branches and to the location of the stenosis. To help maneuver the catheters into place, physicians first insert a more maneuverable guidewire through the vessel and branches to the stenosis location. Then the balloon catheter is slidably inserted over the guidewire to and through the stenosis. After balloon inflation, the catheter and guidewire are removed. A limitation of this approach is that the stenoses must be open enough to permit insertion of the balloon catheter therethrough. Patients who suffer from tight stenoses typically are obliged to undergo the risk and expense of heart bypass surgery.
Prior approaches to address the difficulties of especially narrow stenoses include the use of microdilation probes, dilating guidewires, and similar devices. These approaches have permitted angioplasty treatment to many patients who otherwise would have undergone heart bypass surgery. Approaches such as those of U.S. Pat. Nos. 4,846,174 and 5,102,390 call for insertion of a guidewire, then insertion of the balloon catheter to the stenosis. If the stenosis is too occluded to permit insertion of the uninflated balloon catheter, approaches such as these call for removal of the guidewire while holding the balloon catheter on the proximal side of the stenosis. The physician then inserts a microdilation probe, dilating guidewire, or similar device though the balloon catheter and to and through the stenosis. The microdilation probe and dilating guidewire can consist of a "spring tip" guidewire with a balloon on the proximal side of the tip. The balloon of the microdilation probe, dilating guidewire, or similar device is then inflated, creating an opening sufficiently large to permit insertion of the balloon catheter. The deflated microdilation probe, dilating guidewire, or similar device could be located proximally, distally, or still within the stenosis. Inflation of the balloon catheter further dilates the stenosis.
The present invention improves upon approaches such as these while accomplishing the following objects.
It is a general object of this invention to provide an improved combination catheter device and method of its use, while reducing the steps required to perform an angioplasty procedure.
Another object of this invention is to provide an improved device and procedure which avoid having a guidewire type of member pass distally of a lesion more than once during the entire procedure.
Another object of the present invention is to improve angioplasty devices and procedures so that angioplasty procedures are available to patients who might otherwise require heart bypass surgery.
Another object of this invention is to reduce risk to the patient due to potential disassembly of components while in the body.